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Correlation between cerebral neurotransmitters levels by proton magnetic resonance spectroscopy and HbA1c in patients with type 2 diabetes
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作者 Xiang-Yu Gao Chen-Xia Zhou +5 位作者 Hong-Mei Li Min Cheng Da Chen Zi-Yi Li Bo Feng Jun Song 《World Journal of Diabetes》 SCIE 2024年第6期1263-1271,共9页
BACKGROUND Cognitive dysfunction is the main manifestation of central neuropathy.Although cognitive impairments tend to be overlooked in patients with diabetes mellitus(DM),there is a growing body of evidence linking ... BACKGROUND Cognitive dysfunction is the main manifestation of central neuropathy.Although cognitive impairments tend to be overlooked in patients with diabetes mellitus(DM),there is a growing body of evidence linking DM to cognitive dysfunction.Hyperglycemia is closely related to neurological abnormalities,while often disregarded in clinical practice.Changes in cerebral neurotransmitter levels are associated with a variety of neurological abnormalities and may be closely related to blood glucose control in patients with type 2 DM(T2DM).AIM To evaluate the concentrations of cerebral neurotransmitters in T2DM patients exhibiting different hemoglobin A1c(HbA1c)levels.METHODS A total of 130 T2DM patients were enrolled at the Department of Endocrinology of Shanghai East Hospital.The participants were divided into four groups according to their HbA1c levels using the interquartile method,namely Q1(<7.875%),Q2(7.875%-9.050%),Q3(9.050%-11.200%)and Q4(≥11.200%).Clinical data were collected and measured,including age,height,weight,neck/waist/hip circumferences,blood pressure,comorbidities,duration of DM,and biochemical indicators.Meanwhile,neurotransmitters in the left hippocampus and left brainstem area were detected by proton magnetic resonance spectroscopy.RESULTS The HbA1c level was significantly associated with urinary microalbumin(mALB),triglyceride,low-density lipoprotein cholesterol(LDL-C),homeostasis model assessment of insulin resistance(HOMA-IR),and beta cell function(HOMA-β),N-acetylaspartate/creatine(NAA/Cr),and NAA/choline(NAA/Cho).Spearman correlation analysis showed that mALB,LDL-C,HOMA-IR and NAA/Cr in the left brainstem area were positively correlated with the level of HbA1c(P<0.05),whereas HOMA-βwas negatively correlated with the HbA1c level(P<0.05).Ordered multiple logistic regression analysis showed that NAA/Cho[Odds ratio(OR):1.608,95%confidence interval(95%CI):1.004-2.578,P<0.05],LDL-C(OR:1.627,95%CI:1.119-2.370,P<0.05),and HOMA-IR(OR:1.107,95%CI:1.031-1.188,P<0.01)were independent predictors of poor glycemic control.CONCLUSION The cerebral neurotransmitter concentrations in the left brainstem area in patients with T2DM are closely related to glycemic control,which may be the basis for the changes in cognitive function in diabetic patients. 展开更多
关键词 Type 2 diabetes mellitus Hemoglobin A1c Proton magnetic resonance spectroscopy NEUROTRANSMITTERS Central neuropathy
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7.0T nuclear magnetic resonance evaluation of the amyloid beta(1–40) animal model of Alzheimer's disease: comparison of cytology verification 被引量:6
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作者 Lei Zhang Shuai Dong +1 位作者 Guixiang Zhao Yu Ma 《Neural Regeneration Research》 SCIE CAS CSCD 2014年第4期430-435,共6页
3.0T magnetic resonance spectroscopic imaging brain function in Alzheimer's disease. However, is a commonly used method in the research ot the role of 7.0T high-field magnetic resonance spectroscopic imaging in brain... 3.0T magnetic resonance spectroscopic imaging brain function in Alzheimer's disease. However, is a commonly used method in the research ot the role of 7.0T high-field magnetic resonance spectroscopic imaging in brain function of Alzheimer's disease remains unclear. In this study, 7.0T magnetic resonance spectroscopy showed that in the hippocampus of Alzheimer's disease rats, the N-acetylaspartate wave crest was reduced, and the creatine and choline wave crest was elevated. This finding was further supported by hematoxylin-eosin staining, which showed a loss of hippocampal neurons and more glial cells. Moreover, electron microscopy showed neuronal shrinkage and mitochondrial rupture, and scanning electron microscopy revealed small size hippocampal synaptic vesicles, incomplete synaptic structure, and reduced number. Overall, the results revealed that 7.0T high-field nuclear magnetic resonance spectroscopy detected the lesions and functional changes in hippocampal neurons of Alzheimer's disease rats in vivo, allowing the possibility for assessing the success rate and grading of the amyloid beta (1-40) animal model of Alzheimer's disease. 展开更多
关键词 nerve regeneration Alzheimer's disease 1-40 high-field functional magnetic resonance nuclear magnetic resonance spectroscopy NEUROPATHOLOGY N-ACETYLASPARTATE CREATINE CHOLINE hippocampus NSFC grant neural regeneration
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Urinary nuclear magnetic resonance spectroscopy of a Bangladeshi cohort with hepatitis-B hepatocellular carcinoma: A biomarker corroboration study 被引量:6
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作者 I Jane Cox Abil E Aliev +7 位作者 Mary ME Crossey Mahvish Dawood Mamun Al-Mahtab Sheikh M Akbar Salimur Rahman Antonio Riva Roger Williams Simon D Taylor-Robinson 《World Journal of Gastroenterology》 SCIE CAS 2016年第16期4191-4200,共10页
AIM: To establish if a distinct urinary metabolic profile could be identified in Bangladeshi hepatitis-B hepatocellular carcinoma (HCC) patients compared to cirrhosis patients and controls.METHODS: Urine samples from ... AIM: To establish if a distinct urinary metabolic profile could be identified in Bangladeshi hepatitis-B hepatocellular carcinoma (HCC) patients compared to cirrhosis patients and controls.METHODS: Urine samples from 42 Bangladeshi patients with HCC (39 patients with hepatitis-B HCC), 47 with cirrhosis on a background of hepatitis B, 46 with chronic hepatitis B, and seven ethnically-matched healthy controls were analyzed using nuclear magnetic resonance (NMR) spectroscopy. A full dietary and medication history was recorded for each subject. The urinary NMR data were analyzed using principal component analysis (PCA) and orthogonal partial least squared discriminant analysis (OPLS-DA) techniques. Differences in relative signal levels of the most discriminatory metabolites identified by PCA and OPLS-DA were compared between subject groups using an independent samples Kruskal-Wallis one-way analysis of variance (ANOVA) test with all pairwise multiple comparisons. Within the patient subgroups, the Mann-Whitney U test was used to compare metabolite levels depending on hepatitis B e-antigen (HBeAg) status and treatment with anti-viral therapy. A Benjamini-Hochberg adjustment was applied to acquire the level of significance for multiple testing, with a declared level of statistical significance of P &#x0003c; 0.05.RESULTS: There were significant differences in age (P &#x0003c; 0.001), weight (P &#x0003c; 0.001), and body mass index (P &#x0003c; 0.001) across the four clinical subgroups. Serum alanine aminotransferase (ALT) was significantly higher in the HCC group compared to controls (P &#x0003c; 0.001); serum &#x003b1;-fetoprotein was generally markedly elevated in HCC compared to controls; and serum creatinine levels were significantly reduced in the HCC group compared to the cirrhosis group (P = 0.004). A three-factor PCA scores plot showed clustering of the urinary NMR spectra from the four subgroups. Metabolites that contributed to the discrimination between the subgroups included acetate, creatine, creatinine, dimethyamine (DMA), formate, glycine, hippurate, and trimethylamine-N-oxide (TMAO). A comparison of relative metabolite levels confirmed that carnitine was significantly increased in HCC; and creatinine, hippurate, and TMAO were significantly reduced in HCC compared to the other subgroups. HBeAg negative patients showed a significant increase in creatinine (P = 0.001) compared to HBeAg positive patients in the chronic hepatitis B subgroup, whilst HBeAg negative patients showed a significant decrease in DMA (P = 0.004) in the cirrhosis subgroup compared to HBeAg positive patients. There were no differences in metabolite levels in HCC patients who did or did not receive antiviral treatment.CONCLUSION: Urinary NMR changes in Bangladeshi HCC were identified, corroborating previous findings from Egypt and West Africa. These findings could form the basis for the development of a cost-effective HCC dipstick screening test. 展开更多
关键词 Urinary metabolic profiling Hepatocellular carcinoma nuclear magnetic resonance spectroscopy Hepatitis B Bangladesh
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3.0T 1H magnetic resonance spectroscopy for assessment ofsteatosis in patients with chronic hepatitis C 被引量:6
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作者 Qian Zhang Hui-Mao Zhang +5 位作者 Wen-Qian Qi Yong-Gui Zhang Ping Zhao Jian Jiao Jiang-Bin Wang Chun-Yu Zhang 《World Journal of Gastroenterology》 SCIE CAS 2015年第21期6736-6744,共9页
AIM To investigate the utility of 1H magneticresonance spectroscopy (1H MRS) as a noninvasivetest for steatosis in patients infected with hepatitis Cvirus.METHODS: Ninety patients with chronic hepatitisC and pathol... AIM To investigate the utility of 1H magneticresonance spectroscopy (1H MRS) as a noninvasivetest for steatosis in patients infected with hepatitis Cvirus.METHODS: Ninety patients with chronic hepatitisC and pathology data underwent 3.0T 1H MRS, andthe results of MRS and pathological analysis werecompared.RESULTS: This group of patients included 26 peoplewith mild fatty liver (28.89%), 16 people withmoderate fatty liver (17.78%), 18 people with severefatty liver (20.0%), and 30 people without fatty liver(33.33%). The water peak was near 4.7 parts permillion (ppm), and the lipid peak was near 1.3 ppm.Analysis of variance revealed that differences in thelipid peak, the area under the lipid peak, ratio of thelipid peak to the water peak, and ratio of the areaunder the lipid peak to the area under the waterpeak were statistically significant among the groups.Specifically, as the severity of fatty liver increased, thevalue of each index increased correspondingly. In thepairwise comparisons, the mean lipid peak, area underthe lipid peak, ratio of the lipid peak to the waterpeak, and ratio of the area under the lipid peak to thearea under the water peak were significantly differentbetween the no fatty liver and moderate fatty liver groups, whereas no differences were noted betweenthe severe fatty liver group and the mild or moderatefatty liver group. Area under the ROC curve (AUC) ofarea ratio in lipid and water and ratio in lipid and waterin the no fatty liver group to mild fatty liver group, mildfatty liver group to moderate fatty liver group, andmoderate fatty liver disease group to severe fatty livergroup, were 0.705, 0.900, and 0.975, respectively.CONCLUSION: 1H MRS is a noninvasive techniquethat can be used to provide information on the effectof liver steatosis on hepatic metabolic processes. Thisstudy indicates that the 1H MRS can be used as anindicator of steatosis in patients with chronic hepatitis C. 展开更多
关键词 1H magnetic resonance spectroscopy HEPATITISC ANTIVIRAL THERAPY
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Using Nuclear Magnetic Resonance and MS/MS Spectroscopy for the Identification of Brodimoprim Metabolites in Rat Urine 被引量:1
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作者 Chun YANG Wen Yi HE +4 位作者 Li Jun LI Rui Ming XU Shou Ren ZHANG Zeper ABLIZ Yi Kang SI 《Chinese Chemical Letters》 SCIE CAS CSCD 2001年第6期513-516,共4页
Eight metabolites of brodimoprim (BDP) in rat urine were detected by NMR and ESIMS/MS. They were demethyl-BDP glucuronide, demethyl-BDP sulfurate, demethyl-BDP glucuronide sulfurate, alpha -hydroxyl-BDP, alpha -hydrox... Eight metabolites of brodimoprim (BDP) in rat urine were detected by NMR and ESIMS/MS. They were demethyl-BDP glucuronide, demethyl-BDP sulfurate, demethyl-BDP glucuronide sulfurate, alpha -hydroxyl-BDP, alpha -hydroxyl-BDP glucuronide, BDP sulfurate, N-oxide-BDP sulfurate, and alpha -hydroxyl-N-oxide-BDP sulfurate. All the sulfurates are reported for the first time. 展开更多
关键词 nuclear magnetic resonance spectroscopy MS/MS spectroscopy METABOLITES BRODIMOPRIM
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Nuclear magnetic resonance spectroscopy is highly sensitive for lipid-soluble metabolites 被引量:1
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作者 Haiyang Dai Bikai Hong +4 位作者 Zhifeng Xu Lian Ma Yaowen Chen Yeyu Xiao Renhua Wu 《Neural Regeneration Research》 SCIE CAS CSCD 2013年第22期2103-2110,共8页
Although the water-soluble metabolite profile of human mesenchymal stem cells is known, the lipid profile still needs further investigation. In this study, methanol-chloroform was used to extract lipid-soluble metabol... Although the water-soluble metabolite profile of human mesenchymal stem cells is known, the lipid profile still needs further investigation. In this study, methanol-chloroform was used to extract lipid-soluble metabolites and perchloric acid was used to extract water-soluble metabolites. Fur- thermore, a dual phase extraction method using methanol-chloroform and water was used to obtain both water and lipid fractions simultaneously. All metabolite extractions were analyzed on a 9.4T high-resolution nuclear magnetic resonance spectrometer. Metabolite resonance peaks were as- signed in the acquired spectra according to the chemical shift, and the extraction efficiency of dif- ferent methods was compared. Results showed that in the spectra of water-soluble extracts, major metabolites comprised low molecular weight metabolites, including lactate, acetic acid, fatty acids, threonine, glutamic acid, creatine, choline and its derivatives, while in the spectra of lipid-soluble extracts, most metabolites were assigned to fatty acids. Among the different extraction procedures, perchloric acid was more efficient in extracting water-soluble metabolites and methanol-chloroform was efficient in extracting organic components compared with the dual phase extraction method. Nuclear magnetic resonance spectroscopy showed that as low as 0.7 mg organic yield was enough to obtain clear resonance peaks, while about 6.0 mg water-soluble yield was needed to obtain rela- tively favorable spectral lines. These results show that the efficiency of extracting water and lipid fractions is higher using perchloric acid and methanol-chloroform compared with dual phase ex- traction and that nuclear magnetic resonance spectroscopy is highly sensitive for analyzing lipid-soluble extracts. 展开更多
关键词 neural regeneration nuclear magnetic resonance spectroscopy mesenchymal stem cells metabo-lite profiles extraction method optimization WATER-SOLUBLE lipid-soluble perchloric acid metha-nol-chloroform grants-supported paper NEUROREGENERATION
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Applications of multi-nuclear magnetic resonance spectroscopy at 7T 被引量:2
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作者 Mary C Stephenson Frances Gunner +6 位作者 Antonio Napolitano Paul L Greenhaff Ian A MacDonald Nadeem Saeed William Vennart Susan T Francis Peter G Morris 《World Journal of Radiology》 CAS 2011年第4期105-113,共9页
AIM: To discuss the advantages of ultra-high field (7T) for 1H and 13C magnetic resonance spectroscopy (MRS) studies of metabolism.METHODS: Measurements of brain metabolites were made at both 3 and 7T using 1H MRS. Me... AIM: To discuss the advantages of ultra-high field (7T) for 1H and 13C magnetic resonance spectroscopy (MRS) studies of metabolism.METHODS: Measurements of brain metabolites were made at both 3 and 7T using 1H MRS. Measurements of glycogen and lipids in muscle were measured using 13C and 1H MRS respectively.RESULTS: In the brain, increased signal-to-noise ratio (SNR) and dispersion allows spectral separation of the amino-acids glutamate, glutamine and γ-aminobutyric acid (GABA), without the need for sophisticated editing sequences. Improved quantification of these metabolites is demonstrated at 7T relative to 3T. SNR was 36% higher, and measurement repeatability (% coefficients of variation) was 4%, 10% and 10% at 7T, vs 8%, 29% and 21% at 3T for glutamate, glutamine and GABA respectively. Measurements at 7T were used to compare metabolite levels in the anterior cingulate cortex (ACC) and insula. Creatine and glutamate levels were found to be significantly higher in the insula compared to the ACC (P < 0.05). In muscle, the increased SNR and spectral resolution at 7T enables interleaved studies of glycogen (13C) and intra-myocellular lipid (IMCL) and extra-myocellular lipid (EMCL) (1H) following exercise and re-feeding. Glycogen levels were significantly decreased following exercise (-28% at 50% VO2 max; -58% at 75% VO2 max). Interestingly, levels of glycogen in the hamstrings followed those in the quadriceps, despite reduce exercise loading. No changes in IMCL and EMCL were found in the study.CONCLUSION: The demonstrated improvements in brain and muscle MRS measurements at 7T will increase the potential for use in investigating human metabolism and changes due to pathologies. 展开更多
关键词 magnetic resonance spectroscopy 13C 1H 7 Tesla GLUTAMATE GLUTAMINE γ-aminobutyric acid
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Investigation of formation of dimeric G-quadruplex of HIV-1 integrase inhibitor by nuclear magnetic resonance 被引量:1
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作者 Hui Hui Li Gu Yuan 《Chinese Chemical Letters》 SCIE CAS CSCD 2008年第9期1108-1110,共3页
In this research, an unusually dimeric G-quadruplex of d(GGGTGGGTGGGTGGGT) (SI), the potent nanomolar HIV-1 integrase inhibitor, was detected by nuclear magnetic resonance (NMR). This result has been confirmed b... In this research, an unusually dimeric G-quadruplex of d(GGGTGGGTGGGTGGGT) (SI), the potent nanomolar HIV-1 integrase inhibitor, was detected by nuclear magnetic resonance (NMR). This result has been confirmed by electrospray ionization mass spectrometry (ESI-MS) and circular dichroism (CD). 展开更多
关键词 G-QUADRUPLEX HIV-1 integrase inhibitor nuclear magnetic resonance
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Conformational Analysis of γ-Butyrolactones by Nuclear Magnetic Resonance Spectroscopy
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作者 Fu An KANG and Cheng Lie YIN (Department of Chemistry Beijing Normal University , Beijing 100875) 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第10期885-888,共4页
A series of trans-4, 5-disubstituted -γ-butyrolactones are found to assume two different envelope conformations by means of nuclear magnetic resonance spectroscopy.
关键词 Conformational Analysis of Butyrolactones by nuclear magnetic resonance spectroscopy
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Crystallochemical Characterizations, Raman Spectroscopy and Studies Nuclear Magnetic Resonance (NMR) of Cu<sub>2</sub>Zn(Sn, Si)S<sub>4 </sub>Compounds for Photovoltaic Applications
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作者 Mohamed Hamdi Messaoud Benamira 《Journal of Materials Science and Chemical Engineering》 2022年第1期24-40,共17页
In this study, Si-doped Cu<sub>2</sub>ZnSnS<sub>4</sub> compounds (Cu<sub>2</sub>ZnSn<sub>1-x</sub>Si<sub>x</sub>S<sub>4</sub>, 0 ≤ x ≤ 1) were... In this study, Si-doped Cu<sub>2</sub>ZnSnS<sub>4</sub> compounds (Cu<sub>2</sub>ZnSn<sub>1-x</sub>Si<sub>x</sub>S<sub>4</sub>, 0 ≤ x ≤ 1) were prepared by solid state reaction method for use of materials for photovoltaic cells. The structural and spectroscopic properties of the as-prepared compounds were studied by X-ray diffraction (XRD), <sup>119</sup>Sn, <sup>29</sup>Si and <sup>65</sup>Cu Magic Angle Spinning nuclear magnetic resonance (MAS NMR) and Raman spectroscopy. The Si-substitution in the Sn-site induces three different types of XRD patterns which depend largely on the Si content in the compound. For 0 ≤ x ≤ 0.5, XRD analysis reveals the presence of a pure tetragonal phase of solid solution with I-42m as a space group. Mixed tetragonal and orthorhombic phases were observed for 0.5 < x < 0.8, followed by a pure orthorhombic structure with a space group Pmn2<sub>1</sub> at high content of Si (x ≥ 0.8). <sup>119</sup>Sn MAS NMR spectra show the presence of Sn/Si disorder as a function of the Si content. The <sup>65</sup>Cu MAS NMR spectra of the quadratic solid solution confirm the presence of the two copper sites (Cu-2a and Cu-2c) at 780 ppm while in the case of the orthorhombic solid solution samples, a very broad band is observed. The optical properties were investigated of all compounds by UV-Vis diffuse reflectance and the obtained optical band gap values (1.31 to 2.43 eV) confirm a semiconductor character. 展开更多
关键词 Photovoltaic Cells Cu2ZnSnS4 nuclear magnetic resonance Raman spectroscopy
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Proton nuclear magnetic resonance-based metabonomic models for non-invasive diagnosis of liver fibrosis in chronic hepatitis C:Optimizing the classification of intermediate fibrosis 被引量:3
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作者 Andrea Dória Batista Carlos Jonnatan Pimentel Barros +7 位作者 Tássia Brena Barroso Carneiro Costa Michele Maria Goncalves de Godoy Ronaldo Dionísio Silva Joelma Carvalho Santos Mariana Montenegro de Melo Lira Norma ThoméJucá Edmundo Pessoa de Almeida Lopes Ricardo Oliveira Silva 《World Journal of Hepatology》 CAS 2018年第1期105-115,共11页
AIM To develop metabonomic models(MMs), using 1 H nuclear magnetic resonance(NMR) spectra of serum, to predict significant liver fibrosis(SF: Metavir ≥ F2), advanced liver fibrosis(AF: METAVIR ≥ F3) and cirrhosis(C:... AIM To develop metabonomic models(MMs), using 1 H nuclear magnetic resonance(NMR) spectra of serum, to predict significant liver fibrosis(SF: Metavir ≥ F2), advanced liver fibrosis(AF: METAVIR ≥ F3) and cirrhosis(C: METAVIR = F4 or clinical cirrhosis) in chronic hepatitis C(CHC) patients. Additionally, to compare the accuracy of the MMs with the aspartate aminotransferase to platelet ratio index(APRI) and fibrosis index based on four factors(FIB-4). METHODS Sixty-nine patients who had undergone biopsy in the previous 12 mo or had clinical cirrhosis were included. The presence of any other liver disease was a criterion for exclusion. The MMs, constructed using partial least squares discriminant analysis and linear discriminant analysis formalisms, were tested by cross-validation, considering SF, AF and C. RESULTS Results showed that forty-two patients(61%) presented SF, 28(40%) AF and 18(26%) C. The MMs showed sensitivity and specificity of 97.6% and 92.6% to predict SF; 96.4% and 95.1% to predict AF; and 100% and 98.0% to predict C. Besides that, the MMs correctly classified all 27(39.7%) and 25(38.8%) patients with intermediate values of APRI and FIB-4, respectively. CONCLUSION The metabonomic strategy performed excellently in predicting significant and advanced liver fibrosis in CHC patients, including those in the gray zone of APRI and FIB-4, which may contribute to reducing the need for these patients to undergo liver biopsy. 展开更多
关键词 Metabolomics nuclear magnetic resonance spectroscopy Chronic HEPATITIS C Liver FIBROSIS Surrogate MARKERS
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Nuclear magnetic resonance based metabolomics and liverdiseases:Recent advances and future clinical applications 被引量:7
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作者 Roland Amathieu Mohamed Nawfal Triba +4 位作者 Corentine Goossens Nadia Bouchemal Pierre Nahon Philippe Savarin Laurence Le Moyec 《World Journal of Gastroenterology》 SCIE CAS 2016年第1期417-426,共10页
Metabolomics is defined as the quantitative measurement of the dynamic multiparametric metabolic response of living systems to pathophysiological stimuli or genetic modification.It is an"omics"technique that... Metabolomics is defined as the quantitative measurement of the dynamic multiparametric metabolic response of living systems to pathophysiological stimuli or genetic modification.It is an"omics"technique that is situated downstream of genomics,transcriptomics and proteomics.Metabolomics is recognized as a promising technique in the field of systems biology for the evaluation of global metabolic changes.During the last decade,metabolomics approaches have become widely used in the study of liver diseases for the detection of early biomarkers and altered metabolic pathways.It is a powerful technique to improve our pathophysiological knowledge of various liver diseases.It can be a useful tool to help clinicians in the diagnostic process especially to distinguish malignant and non-malignant liver disease as well as to determine the etiology or severity of the liver disease.It can also assess therapeutic response or predict drug induced liver injury.Nevertheless,the usefulness of metabolomics is often not understood by clinicians,especially the concept of metabolomics profiling or fingerprinting.In the present work,after a concise description of the different techniques and processes used in metabolomics,we will review the main research on this subject by focusing specifically on in vitro proton nuclear magnetic resonance spectroscopy based metabolomics approaches in human studies.We will first consider the clinical point of view enlighten physicians on this new approach and emphasis its future use in clinical"routine". 展开更多
关键词 Metabolomics In VITRO nuclear magneticresonance spectroscopy LIVER DISEASES CIRRHOSIS
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Three dimensional structure prediction and proton nuclear magnetic resonance analysis of toxic pesticides in human blood plasma 被引量:1
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作者 Amit Kumar Sharma Rajeev Kumar Tiwari Mulayam Singh Gaur 《The Journal of Biomedical Research》 CAS 2012年第3期170-184,共15页
The purpose of this study was to investigate the nuclear magnetic resonance (NMR) assignments of hydrolyzed products extracted from human blood plasma. The correlations between chemical, functional and structural pr... The purpose of this study was to investigate the nuclear magnetic resonance (NMR) assignments of hydrolyzed products extracted from human blood plasma. The correlations between chemical, functional and structural prop- erties of highly toxic pesticides were investigated using the PreADME analysis. We observed that toxic pesticides possessed higher molecular weight and, more hydrogen bond donors and acceptors when compared with less toxic pesticides. The occurrence of functional groups and structural properties was analyzed using ~H-NMR. The ~H- NMR spectra of the phosphomethoxy class of pesticides were characterized by methyl resonances at 3.7-3.9 ppm (8) with the coupling constants of 11-16 Hz (Je-cns). In phosphoethoxy pesticides, the methyl resonance was about 1.4 ppm (8) with the coupling constant of 10 Hz (Je-cH2) and the methylene resonances was 4.2-4.4 ppm (8) with the coupling constant of 0.8 Hz (Jp-cH3), respectively. Our study shows that the values of four parameters such as chemical shift, coupling constant, integration and relaxation time correlated with the concentration of toxic pesticides, and can be used to characterise the proton groups in the molecular structures of toxic pesticides. 展开更多
关键词 ^1h-nmr toxic pesticide nuclear magnetic resonance (NMR) parameter relaxation time computa- tional tool data interpretation
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Substituent, Temperature and Solvent Effects on the Keto-Enol EQUILIBRIUM in <i>&beta;</i>-Ketoamides: A Nuclear Magnetic Resonance Study
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作者 Sergio L. Laurella Manuel González Sierra +1 位作者 Jorge J. P. Furlong Patricia E. Allegretti 《Open Journal of Physical Chemistry》 2013年第4期138-149,共12页
Substituent, temperature and solvent effects on tautomeric equilibria in several β-ketoamides have been investigated by means of nuclear magnetic resonance spectroscopy (NMR). Keto-enol equilibrium predominates over ... Substituent, temperature and solvent effects on tautomeric equilibria in several β-ketoamides have been investigated by means of nuclear magnetic resonance spectroscopy (NMR). Keto-enol equilibrium predominates over the amide-imidol one. The relative stability of the individual tautomers and the corresponding equilibrium shifts are explained considering electronic and steric effects and tautomer stabilization via internal hydrogen bonds. In solution, these compounds exist mainly as ketoamide and Z-enolamide tautomers, both presenting intramolecular hydrogen bonds. 展开更多
关键词 β-Ketoamides Keto-Enol EQUILIBRIUM nuclear magnetic resonance spectroscopy
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Molecular structure characterization of middle-high rank coal via^(13)C NMR,XPS,and FTIR spectroscopy
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作者 Xiao-ming Ni Jing-shuo Zhang +1 位作者 Xiao-kai Xu Bao-yu Wang 《China Geology》 CAS CSCD 2024年第4期702-713,共12页
Elemental analysis,nuclear magnetic resonance carbon spectroscopy(^(13)C-NMR),X-ray photoelectron spectroscopy(XPS)and Fourier transform infrared spectroscopy(FTIR)experiments were carried out to determine the existen... Elemental analysis,nuclear magnetic resonance carbon spectroscopy(^(13)C-NMR),X-ray photoelectron spectroscopy(XPS)and Fourier transform infrared spectroscopy(FTIR)experiments were carried out to determine the existence of aromatic structure,heteroatom structure and fat structure in coal.MS(materials studio)software was used to optimize and construct a 3D molecular structure model of coal.A method for establishing a coal molecular structure model was formed,which was“determination of key structures in coal,construction of planar molecular structure model,and optimization of three-dimensional molecular structure model”.The structural differences were compared and analyzed.The results show that with the increase of coal rank,the dehydrogenation of cycloalkanes in coal is continuously enhanced,and the content of heteroatoms in the aromatic ring decreases.The heteroatoms and branch chains in the coal are reduced,and the structure is more orderly and tight.The stability of the structure is determined by theπ-πinteraction between the aromatic rings in the nonbonding energy EN.Key Stretching Energy The size of EB determines how tight the structure is.The research results provide a method and reference for the study of the molecular structure of medium and high coal ranks. 展开更多
关键词 Molecular structure model Carbon-13 nuclear magnetic resonance(NMR) X-ray photoelectron spectroscopy(XPS) Fourier transform infrared spectroscopy(FTIR) COAL
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Fingerprinting Analysis of Rhizoma Chuanxiong of Commercial Types using ~1H Nuclear Magnetic Resonance Spectroscopy and High Performance Liquid Chromatography Method 被引量:13
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作者 Hai-Lin Qin An-Jun Deng Guan-Hua Du Peng Wang Jin-Lan Zhang Zhi-Hong Li 《Journal of Integrative Plant Biology》 SCIE CAS CSCD 2009年第6期537-544,共8页
The ^1 H nuclear magnetic resonance (^1 H NMR) fingerprints of fractionated non-polar extracts (control substance for a plant drug (CSPD) A) from Rhizoma chuanxiong, the rhizomes of Ligusticum chuanxiong Hort., ... The ^1 H nuclear magnetic resonance (^1 H NMR) fingerprints of fractionated non-polar extracts (control substance for a plant drug (CSPD) A) from Rhizoma chuanxiong, the rhizomes of Ligusticum chuanxiong Hort., of seven specimens from different sources were measured on Fourier Transform (FT)-NMR spectrometer and assigned by comparing them with the ^1 H NMR spectra of the isolated pure compounds. The ^1 H NMR fingerprints showed exclusively characteristic resonance signals of the major special constituents of the plant. Although the differences in the relative intensity of the ^1H NMR signals due to a discrepancy in the ratio of the major constituents among these samples could be confirmed by high performance liquid chromatography analysis, the general features of the ^1H NMR fingerprint established for an authentic sample of the rhizomes of L. chuanxiong e. hibited exclusive data from those special compounds and can be used for authenticating L. Chuanxiong species. 展开更多
关键词 control substance for a plant drug A ^1 H nuclear magnetic resonance fingerprint high performance liquid chromatography Ligusticumchuanxiong phenylpropenoid phthalides.
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基于FTIR和~1H-NMR方法分析高压脉冲电场技术对抗氧化肽KWFH的结构影响 被引量:6
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作者 王莹 邢杰 +1 位作者 李幸芳 殷涌光 《食品科学》 EI CAS CSCD 北大核心 2017年第1期116-120,共5页
为了探究高压脉冲电场(pulsed electric field,PEF)提高抗氧化肽活性的机制,以抗氧化肽KWFH为实验材料,以1,1-二苯基-2-三硝基苯肼为衡量指标,通过双因素试验方案,考察电场强度和电场频率对其活性的影响。经过频率2 400 Hz、电场强度10 ... 为了探究高压脉冲电场(pulsed electric field,PEF)提高抗氧化肽活性的机制,以抗氧化肽KWFH为实验材料,以1,1-二苯基-2-三硝基苯肼为衡量指标,通过双因素试验方案,考察电场强度和电场频率对其活性的影响。经过频率2 400 Hz、电场强度10 k V/cm的PEF处理,抗氧化肽KWFH活性提高了13.92%(P<0.05)。借助傅里叶变换红外光谱(Fourier transform infrared spectroscopy,FTIR)、核磁共振氢谱(nuclear magnetic resonance,1H-NMR)、Zeta电位及圆二色谱技术,分析高压脉冲电场技术对其结构的影响。FTIR分析结果显示,经过PEF处理的样品羧酸羰基C=O和苯环吸收峰强度增强;经过1H-NMR分析,推测羧酸羰基C=O和苯环吸收强度变化引起官能团携带的氢质子变化。同时,经过PEF处理抗氧化肽KWFH的Zeta电位提高了8.70 m V(P<0.05),进一步推测经过PEF处理,抗氧化肽KWFH结构更加无序,致使官能团暴露,吸收峰强度发生变化,引起肽活性改变。研究发现PEF处理对二级结构之间转化没有影响。这些研究为进一步探究PEF技术提高抗氧化肽活性机理提供了理论依据。 展开更多
关键词 高压脉冲电场 抗氧化肽 傅里叶变换红外光谱 核磁共振
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核磁共振氢谱法(~1H-NMR)测定西他沙星标准物质的含量 被引量:3
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作者 张芬芬 蒋孟虹 +2 位作者 孙林林 毛黎顺 沈文斌 《西北药学杂志》 CAS 2015年第2期137-141,共5页
目的建立核磁共振氢谱法测定西他沙星标准物质的绝对含量。方法采用Bruker AVANCE-500型和AVANCE-300型仪器,分别以盐酸吉西他滨和齐多夫定为内标,西他沙星中质子信号在δ8.69,δ7.76,δ3.43和δ3.14,盐酸吉西他滨质子信号在δ8.12,δ6... 目的建立核磁共振氢谱法测定西他沙星标准物质的绝对含量。方法采用Bruker AVANCE-500型和AVANCE-300型仪器,分别以盐酸吉西他滨和齐多夫定为内标,西他沙星中质子信号在δ8.69,δ7.76,δ3.43和δ3.14,盐酸吉西他滨质子信号在δ8.12,δ6.21和δ6.02,齐多夫定中质子信号在δ7.61和δ6.01作为定量峰,0.5 mL DMSO-d6∶氚代盐酸(DCl,44.8mg·L^-1)=4∶1为溶剂,测定条件为:探头温度303K,谱宽11.0,中心频率4.9,脉冲序列为zg 30°,延迟时间20s,采样次数32次,窗函数0.3Hz。结果在此条件下,样品与内标盐酸吉西他滨及齐多夫定的定量峰分离良好,进样精密度及重复性较好,线性范围宽,样品与内标盐酸吉西他滨和齐多夫定质量比分别在0.354 9~1.343 9和0.312 4~1.189 2范围内,其线性拟合方程分别为:Y=1.440 9X+0.017 8(r=1.000 0,n=5),Y=1.634 6X+0.008 5(r=0.999 9,n=5)。结果西他沙星的含量分别为99.26%(RSD为0.06%)和99.22%(RSD为0.17%)。结论该方法准确、专属、简便、快速,适用于该药物标准物质的绝对含量测定。 展开更多
关键词 核磁共振氢谱法 西他沙星 含量测定
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基于~1H-NMR的原发性肝癌脾虚湿盛证患者尿液代谢组学研究 被引量:3
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作者 王东 李晶洁 《实用癌症杂志》 2019年第6期878-881,共4页
目的 通过对原发性肝癌脾虚湿盛证患者尿液代谢组学研究,以探讨原发性肝癌脾虚湿盛证患者代谢变化机理。方法 选取35例脾虚湿盛证肝癌患者、35例非脾虚湿盛证肝癌患者和40例和平质健康体检者的尿液进行核磁共振氢谱检测(proton nuclear ... 目的 通过对原发性肝癌脾虚湿盛证患者尿液代谢组学研究,以探讨原发性肝癌脾虚湿盛证患者代谢变化机理。方法 选取35例脾虚湿盛证肝癌患者、35例非脾虚湿盛证肝癌患者和40例和平质健康体检者的尿液进行核磁共振氢谱检测(proton nuclear magnetic resonance spectroscopy,1H-NMR),谱图积分结果使用正交偏最小二乘判别分析法(partial least square discriminant analysis,PLS-DA)进行分析。结果 原发性肝癌患者尿中肌酐、马尿酸、氧化三甲胺(TMAO)、柠檬酸、丙氨酸、亮氨酸、谷氨酸含量均较较对照组健康人低(P<0.01),且脾虚湿盛证组低于非脾虚湿盛证组(P<0.05);而牛磺酸、琥珀酸的含量显著高于对照组,且脾虚湿盛证组高于非脾虚湿盛证组(P<0.05),差异具有统计学意义。原发性肝癌患者尿中乙酸含量显著性高于对照组(P<0.05),而在脾虚湿盛证组与非脾虚湿盛证组中比较,无统计学差异。结论 原发性肝癌患者存在糖代谢、脂类代谢、氨基酸分解代谢紊乱,且原发性肝癌脾虚湿盛证患者体内多种生命代谢的紊乱程度较非脾虚湿盛证患者严重。 展开更多
关键词 核磁共振氢谱检测 原发性肝癌 脾虚湿盛证 尿液 代谢组学
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基于^(1)H-NMR的冠心病血瘀证、痰浊证的代谢组学研究 被引量:12
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作者 易敏 戴幸平 +3 位作者 李秋霞 赵玉航 聂闪闪 王东生 《中南大学学报(医学版)》 CAS CSCD 北大核心 2021年第6期591-600,共10页
目的:冠心病以其极高的发病率严重威胁着人类的健康,对冠心病药物治疗及作用靶点的研究仍非常迫切。本研究旨在运用核磁共振氢谱(^(1)H nuclear magnetic resonance spectroscopy,^(1)H-NMR)代谢组学技术建立冠心病血瘀证及痰浊证的指... 目的:冠心病以其极高的发病率严重威胁着人类的健康,对冠心病药物治疗及作用靶点的研究仍非常迫切。本研究旨在运用核磁共振氢谱(^(1)H nuclear magnetic resonance spectroscopy,^(1)H-NMR)代谢组学技术建立冠心病血瘀证及痰浊证的指纹代谢图谱,寻找这2种证型的血浆标志性代谢物,并揭示血府逐瘀汤治疗冠心病血瘀证的机制。方法:采集符合纳入标准的69例冠心病血瘀证患者、60例冠心病痰浊证患者及40例健康对照受试者的清晨空腹血浆,基于^(1)H-NMR构建冠心病血瘀证及痰浊证的^(1)H-NMR指纹代谢图谱。使用多元统计分析方法主成分分析(principal component analysis,PCA)、正交化偏最小二乘判别分析(orthogonal partial least squares discriminant analysis,OPLS-DA)寻找冠心病血瘀证及冠心病痰浊证的标志性代谢物。随机抽取冠心病血瘀证患者30例,予血府逐瘀汤治疗30 d,对治疗前后的清晨空腹血浆进行^(1)H-NMR检测,分析冠心病血瘀证患者服药前后标志性代谢物的变化。结果:冠心病血瘀证组与对照组存在显著性差异的代谢物有以下15种:3-羟基丁酸、乳酸、丙氨酸、谷氨酸、谷氨酰胺、丙酮酸、磷脂酰胆碱、甘油磷脂酰胆碱、甘氨酸、葡萄糖、苯丙氨酸、柠檬酸、酪氨酸、甲酸盐、极低密度脂蛋白,除葡萄糖、3-羟基丁酸、极低密度脂蛋白水平升高外,其他12种代谢物水平均下降。冠心病痰浊证组与对照组存在显著性差异的代谢物有以下16种:缬氨酸、乳酸、丙氨酸、N-乙酰-β-葡萄糖苷酶、谷氨酸、谷氨酰胺、丙酮酸、肌酸、胆碱、甘氨酸、葡萄糖、苯丙氨酸、柠檬酸、组氨酸、酪氨酸、甲酸盐,除葡萄糖和胆碱2种水平升高外,其他14种代谢物水平均下降。冠心病血瘀证患者服用血府逐瘀汤治疗后胆碱、磷脂/甘油磷脂类、肌酸、脂质、柠檬酸水平升高,乳酸水平下降。结论:^(1)H-NMR结合多元统计学方法能够建立诊断冠心病血瘀证和痰浊证证型的有效模型,找到证型相关标志性代谢物;血府逐瘀汤可通过调节脂质代谢、能量代谢治疗冠心病血瘀证。 展开更多
关键词 冠心病血瘀证 冠心病痰浊证 代谢组学 核磁共振氢谱 血府逐瘀汤
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